Madrid, 27 years old (European press)
Coral reefs are in trouble. Around the world, diverse and dynamic ecosystems are experiencing significant impacts year after year.
The Great Barrier Reef has lost half of its coral since 1995. Scientists are seeing a similar decline in coral reefs from Hawaii to the Florida Keys and throughout the Indian and Pacific Oceans.
The widespread decline is partly due to climate-induced heat waves, which are heating the world’s oceans and causing what is known as coral bleaching, thus breaking the mutually beneficial relationship between coral reefs and resident algae. But there are also other factors that contribute to the degradation of coral reefs, such as pollution and overfishing.
According to a new study published in the journal Science, the key to surviving climate-induced heat waves and subsequent bleaching is managing global climate change and local conditions.
“We found a strong indication that local conditions influence coral outcomes after heat stress events,” said Marie Donovan, lead author of the study and associate professor at the School of Geosciences and Urban Planning. United States of America.
“Although some have argued that climate change is so overwhelming that maintaining coral reefs on a local scale is pointless, our study found that local impacts on coral reefs doubled the effects of climate-induced heat waves.” This indicates that local work to conserve reefs can help coral reefs resist the impacts of climate change. ”
The local conditions for coral reef survival are often underestimated, leaving those who depend on coral reefs for their livelihoods or their managers in despair. However, coral reefs are very important.
“Coral reefs are important at a fundamental level of biodiversity,” recalls Donovan, who is also a member of the ASU Center for Global Discovery and Conservation Science.
Two local problems that can have a major impact on coral reef health are nutrient pollution and overfishing. Overfishing reduces the number of fish that eat algae and maintains the balance of the coral reef ecosystem. For example, depletion of herbivorous fish populations can lead to an abundance of macroalgae, which may indicate a stressed ecosystem.
On the other hand, nutrient pollution from land, including runoff from golf courses, agriculture and urban development along the coasts, significantly threatens coral reefs.
However, both overfishing and pollution provide opportunities for management strategies that can increase coral reefs’ resilience to climate change.
Study data were collected worldwide by professional scientists and trained and certified community scientists on behalf of Reef Check. Data collected only during and after one year of the weather-induced bleaching episode was analyzed to determine the health of the coral reefs. Donovan is now applying this research to local efforts to address harmful coral reef conditions.
“Coral reefs occupy one of the smallest areas on the planet, but they are home to the largest number of species from all ecosystems on Earth, and they are also incredibly important to people,” he continues. It depends on coral reefs for their safe food, to protect coasts from storms and to protect other livelihoods. In many parts of the world, it’s not just about beauty, it’s about survival. “